Facebook and Twitter Remarketing Setup

I'm having problem with remarketing campaign on Facebook and Twitter. 1. On facebook, when I create custom audience for retargeting people engaged on my post. I get this error: Unsupported get request. Object with ID '6061124951535' does not exist, cannot be loaded due to missing permissions, or does not support this operation. 2. Twitter, I can't retarget those who engaged on my post. I need someone to tell me how to set it up correctly. On both Facebook and Twitter, I like to retarget everybody who has engaged in my facebook post and engaged in my tweet. I ran a couple campaigns for a couple days, so I have some data, just a few thousand engagements on each. I like to retarget those people. I don't have any tracking codes installed on my site. Because they mess up my site. Both facebook and twitter. I'm not looking to retargeting those who visited my site, so I don't think I need the tracking code on my site yet. I'm only looking to retarget those who engaged on my post and tweet. Looking for someone who's an experienced facebook and twitter advertiser. I just need some instructions. Very small project. $20